William i



(No Model.)

W. D. GRAY.

ROLLER GRINDING MILL.

No. 339,161. Patented Apr. 6, 1886.

WITNESSES INVENTOF? TINITED STATES PATENT Trice.

WILLIAM I). GRAY, OF MILWAUKEE, W'ISCONSIN, ASSIGNOR TO B. P. ALLIS & 00., OF SAME PLACE.

ROLLER GRINDING-MILL.

EBPECIFICATION forming part of Letters Patent No. 339,161, dated April 6, 1886.

Application filed June 23, 1584. Serial No. 135,794.

To all whom, it may concern:

Be it known that I, WILLIAM D. GRAY, of Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Roller Grinding- Mills, of which the following is aspecification.

This invention relates to those mills in which a horizontal feed-roll delivers the material to be treated from a hopper to and between a pair of reduction-rolls.

The aim of the invention is to provide an improved mechanism for effecting the stoppage of the feed-roll as 1110 grinding-rolls are spread or separated, and vice versa; and to this end it consists, essentially, in the combination of a driving-pulleyon one of the grinding-rolls, a pulley on the feedroll shaft, and an intermediate connecting-pulley connected with and moved by the roll-adjusting mechanism, in the manner hereinafter explained and claimed.

Roller mills are commonly built in two forms-one with a single pair of rolls, known as single mills, and the other with two pairs of rolls, known as double mills. In the double mills the two pairs of rolls and their sustaining, adjusting, and feeding devices are duplicates of the other.

As my improvements are applicable to the double mills by simply duplicating the parts used in a singlemill, I have in the accompanying drawings shown both forms of embodiment.

Figure 1 represents a side elevation of the single mill; Fig. 2, alikeviewof a double mill.

Referring to Fig. 1, A represents the frame of the mill; B, a grinding-roll in fixed bearings; G, the co-operating roll in swinging bearings or arms 1), so that it may be moved to and from its companion. A rod, E, connected by adjustable yielding devices to the bearing D, extends thence to an eccentric, F, on a rockshaft, G, sustained in fixed bearings. This mechanism is duplicated at the opposite side of the mill, both eccentrics being mounted on one shaft, which is provided with a crank-arm, H, attached to an operating-rod, I, the movement of whicheffects the adjustment of both ends of the roll. At its top the machine has a feed-hopper, .I, provided at its mouth with {No model.)

afeed-roll, K, to deliver the material to the grinding-rolls.

All of the foregoing parts are of ordinary form and arrangement, and are not claimed herein.

In applying my improvement I provide the feed-roll at one end with a driving-pulley, L, attach to one of the grinding-rolls adriving pulley, N, and introduce between the two a third pulley, M, which serves by frictional 6o engagement to transmit motion from one directly to the other. This intermediate pulley is carried by an arm, Q, secured firmly but adjustably by a screw, (1, to the roll adjusting or spreading rod E. \Vhen the handle I is operated to close the rolls, the rod E carries forward the pulley M, forcing and holding the same in intimate contact with the pulleys L N, so that motion will be transmitted positively and noiselessly to the feed-roll. The reverse movement of the parts, to spread the rolls, disconnects the pulley M and stops the feed-roll. The adjustable connection of the arm Q to the adjusting-rod permits compen' sation for wear of the pulleys, and for changing positions of the rod E, and permits the operative pressure of the pulley M to be in creased or diminished, as may he demanded.

In the double mill shown in Fig. 2 each pair of rolls is adjusted and provided with feedcontrolling mechanism, as in the single mill; but the two feed mechanisms are connected to one and the same operating-rod, I.

Vhile it is preferred to carry the pulley M by the rod IE, it may be carried by the movable roll-supports D.

I am aware that feed-driving devices and rollspreading devices have been combined for joint operation in various forms, and that a belt for driving the feed-roll has been tighto ened and loosened by an idler or tightening pulley operated by the roll-spreading mechanism, and to such eonstructionI lay no claim.

In my arrangement belts are wholly dispensed-with, and the cost of construction, as compared with the belting system, materially reduced.

I do not specifically claim herein the precise arrangement of devices represented in my application No. 138,782, filed July 25, 188i, roo

although said mechanism constitutes a special form of the invention covered by the generic claims herein.

2. In a grinding-mill, the combination of the hopper, the feed-roll, the stationary and the movable grinding-rolls, the friction driving-pulley secured to one of the grinding-rolls, the friction-pulley secured to the feed-roll, the movable roll-bearing 1), its adjusting-rod E, and the pulley M, carried by said rod and arranged to engage directly with both of the first-named pulleys, as described and shown.

W'ILLIAM D. GRAY.

W itn esses:

RICHARD HOPPIN, RICHARD BIRKHOLZ. 

